CDL Exam Information and Testing Procedures

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TSImageskd187743sdcThose persons wishing to drive a tractor-trailer are required to have CDL training and to hold a valid Class A commercial driver’s license, commonly referred to as a CDL. The CDL was created by an act of Congress known as The Commercial Motor Vehicle Safety Act of 1986 which was signed into law on October 27, 1986.

The CDL ensures the truck driving schools meet the minimum requirements for the safe operation of a tractor trailer through testing and licensing standards. The Act also makes it illegal for a driver to hold more than one type of license. Although the Act is a Federal law, each state, from California all the way to Texas, retained the right to license drivers with the adoption of the standards. A CDL has been required to drive a tractor trailer since April 1, 1992. To obtain a CDL, the truck driver must pass a knowledge and driving skills test administered by their state – they initially train for this in a truck driving school. The skills test must be the type of vehicle which the driver intends to be licensed.

Truck drivers need a class A CDL in order to drive a tractor trailer. The class A vehicle type has been designated as "any combination of vehicles with a GVWR of 26,001 or more pounds provided the GVWR of the vehicle(s) being towed is in excess of 10,000 pounds.” – Federal Highway Administration (FHWA)

In addition to the standard general knowledge test required for a CDL, truck drivers must also obtain endorsements on their CDL to legally operate a tractor trailer. Drivers need to pass the combination vehicle and air brake knowledge tests and skills test on a vehicle with these features. Failure to pass these components will result in a restriction on the driver’s CDL. Some of the more common endorsements for most professional truck drivers are:

  • T - Double/Triple Trailers (Knowledge Test only)
  • P - Passenger (Knowledge and Skills Tests)
  • N - Tank Vehicle (Knowledge Test only)
  • H - Hazardous Materials (Knowledge Test only)
  • X - Combination of Tank Vehicle and Hazardous Materials

To comply with the standards of The Commercial Motor Vehicle Safety Act of 1986, truck driving schools CDL training program consists of both classroom and behind the wheel training. In the classroom, future professional truck drivers learn about the procedures and techniques to safely operate a tractor trailer. Student truck drivers must also be aware of the laws that govern operating a commercial motor vehicle and proper log book practices. Classroom instruction at truck driving schools includes practical instruction on map reading and trip planning for the professional truck driver. Behind the wheel time consists of just that – time that is spent behind the wheel of a late model tractor trailer combination applying the truck driving techniques discussed in the classroom. Student truck drivers learn and master the turning, backing and shifting skills on a large, private driving range. Once a student truck driver has gained the experience and confidence of the driving range skills administered by a trucking school, the student and driving instructor proceed with street training to polish the student’s skills in real world situations. All this training is conducted by the trucking school in preparation of the student’s CDL skills test where the future truck driver must demonstrate his knowledge and driving skills in presence of a state-certified CDL examiner.

CDL License Also Requires DOT Qualifications


As part of the qualifications for a CDL license, you also have a DOT physical examination. The qualified medical professional will provide you a ‘Medical Examiner’s Certificate’ if you can meet the medical guidelines the U.S. Department of Transportation has established. To help student truck drivers understand the requirements, TTS has highlighted some of the major conditions below. Please consult the FMCSA website for further information.

  • You must have 20/40 correctable vision in each eye. Glasses or contact lenses are permitted.
  • You cannot be a diabetic on needle-injected insulin; diabetes controlled through a diet or oral medication is permitted.
  • Your blood pressure must be under 160/100. Prescription medication to control blood pressure is permitted.
  • Your blood sugar level must be under 200.
  • Use of a Schedule 1 drug, amphetamine, narcotic or any other habit forming drug is not permitted.
  • If you have a current diagnosis of cardiac insufficiency, collapse, congestive cardiac failure or any other cardiovascular disease you will be required to provide the Medical Examiner with a stress test from within the last 12 months along with a release from your physician stating that you can drive a commercial motor vehicle without restrictions.

Other factors or conditions which could prevent you from obtaining the required DOT clearance include: sleep apnea, a recent back injury, recent major surgery, a current hernia, or a recent workmen's compensation claim. If you have questions about your medical health, please consult your physician before you begin the CDL training program.

In conjunction with the DOT physical, CDL truck drivers are required to take random drug screens throughout the drivers’ employment in the trucking industry. The DOT drug screen will detect the usage of illegal narcotic drugs including cocaine, marijuana, amphetamines, opiates and phencyclidine (PCP). Your chosen truck driving school will most likely provide you with a DOT physical & DOT drug screen during the first week of CDL training. Most Truck Driving Schools will walk you through this process and explain the requirements in full.

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